Railway signaling system.



R. P. TUTTLE.

RAILWAY SIGNALING SYSTEM.

APPLICATION FILED JULY 29,1900.

980,709. Patented Jan.3,1911.

3 SHEETS-SHEET l R. P. TUTTLB. RAILWAY SIGNALING SYSTEM.

APPLICATION FILED JULY 29, 1909. 980,709. Pa en ed Jan. 3, 1911.

a SHEETS-SHEET 2.

lit]

XMI 00:09: CL.

illlh R. P. TUTTLE. RAILWAY SIGNALING SYSTEM.

APPLIGATION FIL ED JULYZQ, 1909.

Patented Jan. 3, 1911.

SN. N

Q vilm cues:

Specification of Letters Patent.

. Application filed July 29, 1909. Serial No. 510,274. I

adapted for use on single traclr railways.

-'In the aipplication of my invention the railway wi be divided into sectionsof any desired lengthandgeach section may be divided into any desired number of blocks each of'which will be protected by signals designed to govern the movement of trailic in either direction. At one end of each section means are provided by which an operator may govern all signals in the section and .thereby establish the direction of trailic desired.

' I will describe a signaling system embodying my invention and then point out the novel features thereof in claims. I

' In the accompanying drawings, Figure 1 is a diagrammatical view of a section of a sngle track'railway, divided into a series "of blocks, equipped with signals to control traffiein either direction and embodying my invention. In this view the signals are set to permit trafiic from left to rig-ht. Fig. 2 is a view similar'to Fig. 1 in which the parts are setto permit traiiic from right to left. Fig. 3 is a View, with the track circuits omitted but otherwise similar toFigs. 1 and 2, showing a modified form of direction controller.

Similarrcference characters designate corresponding parts in all of the figures.

designates a section of a single track railway, divided into blocks 1, 2 and 3. Each block is provided at its entrance end with a signal having ahom'e arm S and a distant arm S, these being shown as mount ed on the same post, but they may, if pre- "ferred, be mounted on separate posts. At the exit end of block 3 when traffic is moving from left to right there. is provided a signal N having 'a home arm only. The same is 5 0 trueof the exit end H of block l; when traffic 15 moving from right to left. There; is thus provided apair of opposing signals'et' the .T

unction of adjacent blockadesignates a battery frgm which cyr rent is supplied to a 's'erieso relays, which Railway: Signaling Sysfollowing is a specifica ing or indicating circuit.

trafiic relays, 5, 6, 7, ,8, 9, 1

Patented Jan. 3, 1911-,

i for the sake of distinction will be termed 0, 11 and v 12.. To

supply the current to these relays two main w res 13 and 14 are employed and a return w1re 15 is common to all of The traffic relays 5, 7, 9

the trailic relays. in

and 11 receive their current from wire 13, and those numbered 6, 8, 10 and 12 from wire 14, and those latter relays are connected to the Fig. 1, while the former battery B in are connected to 5 said' battery inFig. 2. Trafiic relays 6," 8,,

10 and 12 control the tra right and the other relays fromfright to left. In order to determine which set of" traffic relays shall-be operative, I provide 2.

direction controller at one e which comprises a movabl nectcd by a wire 17 to the switch is adapted-to contacts 18 or 19, to which .13 are respectively connecte preferably operated bymc lover C, and a barb and engaging the switch 1 14 13 not In usetraflic relays, it is direction controller. employ another switch. 20 the lever C and barb, to two contacts 21-22.

nected to wire 14 by a tact 21 is connected to te s s nd of the section, e switch 16 conbattery B: Thisthe wires 14 and d. The switch is ans of a pivoted connected to the lever (Sin any desired 1 -manner to positively move the latter in either direction.- VVhen either of the wires 13 or to' supply current to its utilized as part of a lockfor governing the In this ,connection,

85, also operated by engage either of The contact 22 is conwire 24, and the conthe wire 13 by a wire A .wire 25 leads from switch 20 through a solenoid D to wires 63 and 15 and a battery B W'ith the circuits as Fig. l or Fig. 2, 'the solen sized and i clear a locking plate 0 conn shown in either 01d Wlll be ener-;

ts core 'be drawn inwardly to ected to the lever C and provided with two,-r ec'esses 2'6 and 27,

and while in this position operate the lever C in any part of the section.

the operator can' to set the signals to change the direction of trailic. ever, the solenoid become core will drop into one of Should, hofw- 10o denergized, its the recesses 26 C against'movewhen a train is as will be herelnafter explained. In addition to the lock,

may provide an indica adapted to be moved into the solenoid and-so indicat whether or not he' should.

toror signal E two positions by. e to the operator operate-the lever 6 broken again at relay and is closed around},

'tor may be employed to control the locking" 1n position shown armature of tralfic rel and second through :t'ollows: from battery Z to wire 28, armature of trafiic relay 8, w

'trtslucing'similar paths throu h the ti'ack and indicating' There are four tra ck relays indicated by f, g, [L and '1', and six track circuit batteries indicated by j, is, Z, m, n and o. The same track battery doesnotalways supply current to the-same relay. '\-"'hen the parts are in Fig. 1 the batteries Z, 122-, nand 0 supply current to thetrack relays f, hand 5 respectively; The circuit from battery l to relay f nay be traced as 29 of trailic relay 8, wire 30, lower rail of section 1, wire 31, armature 32 of trallic relay 5, wire 83, through rela 7 to wire 34:, armature 35 of trafiic relay 5, wire 36, upper rail of section 1, wire :37, armature 38 ire 39-to battery Z. As the wiring is the same in each case, it is not necessary. to trace out the other circuits. The traffic relaysfi, 8, 10 and 12 are connected in multiple to the-wire 14 andireturn wire 15, as follows: wire 14, wire 40, through traltic' relay 6, wire 11, switcliO,

To reach traliic relay 10, however, the course of the current is from battery B through'switch 16, wire 14, armadrops. Any other it, 8, 10 and 12, which cate danger, Similarly: there is a switch 0 in each of the circuits of are in July 28, 1 s.

part of a looking or indicating circuit. Thus 4 ture 82 of track relay {[01 armature 1 10 of trafiic relay 8, wit-ell, relay 10,-switch O, ay 9, common return wire'l'lfin battery B; It will thus be' observed that the wire 1% is broken at relay 8, but is closed-around-this break in two ways rs't-through armature 82 of track relay g, armature-I 10 of traffic relay 8; The reason, for breaking wire 14 and closing it through armature 82 of track relay 9 is that, when this wire is used for coking purposes, it-inust-include the arma: ture of the track re1ay,' as will be explained hereinafter in connection-with the detailed description of. the locking circuits. Thepurpose of the additional path through, armature 140 of trailic relay 8 is to maintain a closed circuit to tratlic relays 10'and 12 from battery B when track relayg is-subv sequently opened due to the presencev of agage the locking train in. its block. Wire 14 is similarly this break through armatures oftrack relay k and traflic relay 10. The reasons for-not breaking wire 14 at relays Gand 12 and in- I audit. will 'tery which resul trafiic relays at these pointsiwill be herelocking circuits.

Itwillbe observed that there is a switch U in each of the circuits of the. traflic relays switches are operated by the movement of the home arms of the signals which govern traffic from right to left, in, such manner that said switches-will bG'ClOSBd only when said home signals indithe'- traflic relays 5, 7, 9 and 11, which are controlled by the movement of the home arms of the signals which -governthetraffic from left to right and-are closed only when said'home signals position toindicate chanical connections betweeifthehome arms of the si nals and'the'switches Q, and O are indicated on the drawings by dash lines, theseconnections' being Slmllfil" to the mechanical connections shown in Letters Patent N o'. 894,471 granted toJacob B. Struble on As before stated, each of thewires 13 and when not in use to control trafiic forms in Big. 1 the locking circuit can betraced as follows: from battery 13* wires 418, 49, armature 50 of trathc'relay 12, wire 51, wire 13, wire 52, armature 53- of track relay h, wire I 54, wire 13., wire 55, afmature56 of track armature 42 of traflic relay 5 wire 43 to coml "mon return wire 15; wire 14:, wire, 44 through traffic relay 8, wire 4:}, switch 0,

armature 46 of traffic relay 7, wire 47 to coni- I- 'mon return wire 15.

relay 9, wire 57 ,wire- 13, wire 58, armature 59 of track relay f, wire 60, ivire 13, to contact 19, wire-23 to contact 21, switch 20, wire 25, through motor 1), wire 63, wire 15, wires 61 and 62 tobattery B. Asthe parts are. shown 'in Fig. l, the section A is supposed ,to be entirely free of-cars, and locking c1rcuit is closed, the motor energized and its core clear of thelocking plate 0. Should, however, a ltrain or' car be on either ofthe blocks 1 2 or 3, thetrack relay' willbedeene'rgized f, g or 71', respectivel I and the locking circuit broken at such point whereupon thecore of the solenoid will en I latec and so prevent any operation of the quit just described does not include an armature oftrack relay i for the reason that when wire 13 isjin use for looking or indica- 'tion purposes, this-track relay is connected with block y, and in the 'articular arrange. ment-of circuits which I have shown herein, the'lockin circuit is not, controlled by cars or trains eyond the limits of signals H n N' Y. J Referringnow-to Fig; 2, the

ranged to be seen thahthe leverC'has-been operated to connectthe wire 13 5,,37,19 and-l1. In this case t etrac ,g, /1, and i, are energizedby. the bat- ,"lajpl'and in, res actively. The wire 14:, forms part'of the coking circuit, and

with bat in energizin -trafiic danger. The meconsequently the'' ever 0. The locking cirparts arearf permit trafiicjfrom rlght to left,

3O 9 block section X tobattery ,4.

tJaiiic relays 6, 10 and 12 are deenergized,

Also the switches have been opened by the movement of the home arms S of the signals which control trailic from right to left, to safety position, and the switches 0 have been closed by the movement of the opposing honie arms to danger.

The circuit for traific relay is as follows: from battery 13, to wire 17, switch 16, contact 19, wire 13, wire 64, through traffic relay wire (35, switch 0', armature 66 of traiiic relay 6, wire 07 toretur'n wire 15. observed that wire 13 is broken at trailic relays 5, 7 and 9, and that it is closed around these breaks in manners similar to those described in connection with wire 14L of Fig. 1.

it is unnecessary to specifically trace the.

circuits of traihc' relays 7, 9 and 11, as they are similar to that of relay 5, and each in.- cludes a switch 0 and an armature ot' the next succeeding relay, as 8, or 12. Neither is it necessary to trace specifically the circuits of all the track relays, j, g,'/i.

and 2', when the signals are set for tratfic from right to left, but I will trace that of track relay f as follows: from battery to upper rail ofblock section at, to wire 68, armature 09 of trafiic relay 0,.wire 70, through track relay f to wire 71, armature '2' 2 of tratfic relay 6, wire '73 to-lower rail of The locking circuit in Fig. 2 may be traced as follows: from battery B to wire a8, armature 74 of track relay 2', wire 75, armature 76 of tratiic relay 11, wire 77, wire 1 1, wire 78, armature 79 of track relay h, wire 80, wire 14, wire 81, armature 82 of track relay g, wire 83 wire 14, Wire 2 11-, switch 20, wire through motor D, wires 63, 15, 61and 62 to battery 13*. This locking circuit does not includean armature of track relay f for the .reasbn hereinbefore stated in connection withthe locking circuit for Fig. 1 viz. that relay f is at this time connected with block X, and the locking circuits as I have herein shown them are not controlled by the presence of cars or trains beyond the limits of signals H and N.

To avoid unnecessary complication in the drawings, I have omitted the signal circuits, except those for the signals at the junction of blocks 2 and 3, but; it is to be understood that each signal is operated by a circuit similar to those illustrated. The circuits may be traced as follows: Referring to Fig.

1, the circuit for the home arm S of signal M at the entrance to block 3 is from battery B25130 wire 84, armature85 of track relay h,

wires 86, 87, armature 88 of traffic relay 10,

wire 89 through home signal S, wires 90,

91, 92 and 93 to battery. For the distant" signal S at the entrance to the sameblock,

the circuit may be traced as follows! from battery B to wire 8-1, armatures and 94; of track relay 7!, wires 95 and 90, switch 97 Itwill be.

' through distant signal S to wires and .93 to battery E the home arm S of the signal M at the entrack relay it, wire 86, wire 98, armature 99 of trafiicrelay't), wire 100, to home signal S to wires 91,92'and 93 to battery. The circuit for thedistant signal S atthe entrance B to wire 84, armatures 85 and of track relay it, wire 95, wire 101,'switch 102.,

91, 92 and 93 to battery-B Ynals of M and M. are operated by the movement of the corresponding home signals respectively. Thusswitch 102 is operated by the home arm of signal M which protects block 2, and switch 97is operated by the home arm of. signal M; which protects ,block 3.

H, K,'K, etc. These pole-changingswitches lays f, g, h and 2'. Although there are two pole-changers included in each traclrcircutt, one at the battery end of the block and one at the track. relay end of the same block,

.relay end, being operated by the home signal governing trafiic in the opposite direc- 'tion, remains inactive owing to the fact that its operating signal is inactive.

operatedlby the home blade Sof signal K, moves to reverse the polarity of the current in the rails of block 1 when atram enters inactive owing to itsbeing operated by the the apparatus set for trafiic in the direction shown. I

Referring now to,F1g. 3, there is shown a trance to block 21 may be traced as follows:. from battery B to wire 84, armature 85, of

to the same blockis as follows: from battery 7 Thus. in 7 block 1.91" Fig. 1, thepole-changer 12 being block2. Pole-changer 2, however, remains Referring now to Fig. 2the circuit-,for

wire 103, through distant signal S to wires The switches 97 and 102 in the circuits of the distant sig-' Pole-changing switches, designated as 1)," 29 2), etc. are included in the circuit of. track batteries is, Z, m andn, and are-operated respectively by the home arms of "signals control the distant signals S in' the well known manner by governingthe direct on ofcurrent through the polarized track reblade S of signal H, whichis inactive with .ianodifi-ed locking o'rfindicziting mechanism,

which in addition to" performing the func- 100' only one of these, viz. the one at the batteryv I end, is active. The other one, located at the I the circuit is somewhere out efiiirder.

contacts 101 and 10S, and from the other end of said battery a. wire 109 leads to two contacts 110 and 11.1. Two switches 112 and 113 are provided, the first to engage either of the contacts 110015-10", and the second to engage either of the contacts- 108 or 111. These switches 1112 and. 113, with their corr'cspondingcontacts, comprise a pole-changer P, the function of which is to control the polarity of battery 13 through the tra'llid relay circuitsl There is a polarized relay 11.1 inserted in the line wire 1 1. adjacent the signal 11 at the entrance of block 1. There is also a polarized relay 115 inserted in the line wire. 13 adjacent the signal N at the entrance of block 3. l he switch 113 is connected by a wire 116 to the switch 16, which wire takes the place of wire 17 in Figs. 1 and 2. The switches 112 and 113 are operated by the bar hhut only after the bar has moved su'lliciently'to move the switch 16 from contact 18- to contact 19, or vice versa. 'lhe operation of this part of the invention is as follows: Assuming it is desired torevcrse the direction of tra'tlic as setup in Fig. 3, the operator will move one contact to the other, the core of the solenoid D will have dropped into the re cess 105 in the locking plate 0. The parts are to he so proportioned and arranged that the core will engage the end of the reccss when the switches engage the contacts 19 and 22. It now all the tratiic relays and the track relays are operating properly the locking circuit will he closed and the sole noid D will he energized thereby withdrawing its core from recess 105 to permit the operator to complete the stroke of the direction controller. If the solenoid D does not so operate, the operator willknow that In this case the polarized relay 115, although receiving current from thewire 13, will not respond thereto because the polarity ol 'the current from battery B, as controllelildhy the pole-changer P is wrong. The polarized armature 117 or the relay 115 is included in the circuit of the home arm 8 of signal N, which is at the entrance of block 3,*and consequently, such signal circuit will be broken at said armature, until the operator coinpletes the stroke of the controller C and moves the switches 112 and 113 into ongagement with contacts 107 and 111, thereby changes the polarity of the current flowing through wire 13.

Zlhe relay 114C will respond. to current i l (h.

opposite polarity to that to which relay 1131 respoiu s. shown in Fig. 3 the polarity of ihe current is such that relay 11% respon ils thereto. The circuit tor the home arin 01" signal. 11" at entrance of block 1. as shown in L from battery 13 to wire 128, armature 129 of track relay 2', wires 130 and 1.31, armature 132 of traihc relay 11, wire 133, armature 117 of polarized relay 115, wire 13 1, through signal S, and wires 135 and 136 to battery B. As shown in this circuit the armature 132 is disengaged from its contact, as is also the armature 11'1". i l hen the direction control.- le is moved, however, complete stroke as hefore'descrihed, these breaks in the circuit will he closed. By the use of this systenwit is evident that unless all the track relays and tralllc relays have hwn properly operated, in response to a shifting ofthe battery 13 from wire .1 1 to wire 13 or vice versa, the movement of the controlling switch C can not he completed, and thereforefitlie signal governin tratlic into the section cannot be cleared. The advantage of: this system over that disclosed in Figs. 1 and lies in the fact that in the preceding systems it was only essential that the armature contacts of all track relays and oi' the traf ic relay tarthest from the controlling switch should he closed to permit. of a complete reversal of the controllingswitch and a consequent clearing of the signals governing tral'lic in the opposite direction; while in the system of it'is also essential that all signals should move to the danger position, all trai'lic which by the movement of the controlling lever disconnected from hattery B should open their armature contacts, and all trallic relays which are connected with battery B by the movement of th controlling switch should close their armature contacts, before the signal governing tralfic into thesection can be cleared. For example, referring to Fig. .2, assuming that the direction controlling lever should he reversed and that signal hl should fail to move to dai 1 position, signal 11" could be" cleared and. the section would be open to tratlic from both directions. With the addi tional devices of Fig. 3, however, the faihire of signal 1*? to move to danger would hold open the circuit for traiiic r1 0, resulting in trach rela, h being 30th cminected hloclt 3 and consequently holding open their armature contacts whereby the indication circuit would be open and signal 11 could not he cleared. 1 1..

ay 12 at switch ssopoe failure of tratlicrelay 11 to open its contacts would result inthe same conditions as above described, the'circuit for trailic rel'ay l2 being then held open at the back contact of the armature of relay 11. Again, if trafiic relay 12 should fail to close its'a rmature conta ts when connected with battery B, the same conditions would obviously exist. The tailure of a track relay to close its contacts at ter a reversal of the controlling switch, would of course, ghold open the indication circuit directly. A similar explanation holds true "regarding the failure of any signal,

track relay, or trafiicrelay-in Figs. 1 or 2.

' From the foregoing it will be seen that there are opposing signals at thejunction ofadjacent blocks, and that the operation of these signals .is controlled by two sets of trafiic relays, one set being connected to one wireand the other set to another wire, and

' that by means of a direction controller either of said sets of relays may be connected to a-common battery and a common return wire, and thus determine which of the opposing signals; shall be operated. Also that the track relays are common to both sets of opposing signals, and that the traiiic reworking order.

- claim is:

\ '1'. In a signaling system 'for single track lays determine which of the two block sec? tions on either. side of opposing signals shall receivecurrent from a certain battery. Thus in Fig. 1 the track rails'of block 1 receive current from battery Z, while in Fig. 2 the track rails of block 2 receive the current from battery I, and in each case they current is supplied to the track relay in the rear (that is against tratfic) and this allows the .use of the well-known polarized system of track circuits for the control of distant signals as previously referred to. This'particular system ofdistant signal control,

however, forms no part of my present inven-' tion. It will also be seen that one 'set of signals cannotbe moved to indicate safety unless'all of the opposing set of signals have moved to indicate danger and that there can be no change made in the direction of traflic unless the entire section is clear of-cars, and all the relays and circuits are in proper Th'e.wiring for each pair of opposing signalsisthe same in all cases except at the ends ofjthe sect-ion (signals H.H and NN The difl'erence in these .is the 5 elimination of parts which would be ne'ca essary if'there were distant si'gnals' in the rear of signals H and N, and if thelcon; trol of the lock D were desired beyondsignals H and N. I have shown the-locking circuits as controlled only. by care within the limits of track mentioned, butthis con trol Iniay be extended in either direction if ceslre Having described my inentiompwhat' I railways, a section of track divided into a plurality of blocks, a pair of opposing sig nals at each junction of adjacent blocks, two sets of trailic relays, one for controlling the operation of'one set of, signals and the other for controlling the operation of the opposing set of signals, a. source of cur"- With the source of current.

2. In a signaling system .for' s1ngle track railways, a section of trackdivided into a of adjacent blocks, a track relay for each pair of opposing signals and controlling said signals, two sets of traffic relays, one for controlling the operation of one set of spectivly the two sets of'track circuits, a source of current supply for both sets of either set with the source of current.

4. In a signaling system for single track railways a section of track diy'idedinto a of adjacent blocks, a signaling circuit for signals and the ot-herset for controlling the circuits of the opposing set of signals, a source of current supply-for both sets of either set of traliic relays with said'source. 5. In a signaling system for s1ngle ,t;racl' railways, a section of track divided into a opposing signals one pair-at each junction of signal, a track relay or each pairof signals, an armature in" each signal circuit operated battery for each track rel ay,-tw0 track. circuits for each. block; and two.- trafiic 're'lays for 'each' block, each of which traific relays connects the-rails of "its 'block with either a track battery or atrackfirelay. i

6. In a signaling system for smgle'track railways, a plurality of pairs of opposing signals' iirrangd at intervals along'a track rent for energizing both 'sets'of trafic' relays, and means for connecting either set plurality of blocks, a plurality of pairs of opposing signals, one pair at each junctiontrafiie relays, and means for connecting.

plurality of blocks, a plurality of pairs of,

ad acent blocks, a signaling circuit .{EOI each plurality of blocks, a pluralityof pairs of opposing signals, one pair. at each junction signals and the other for controlling the two sets of traiiic relays-for controlling re- 1'00 trafiic' relays and means .for connecting each signal, two setsof trafiic relays, one set for controlling the circuits-of one set ofby thewrrespiinding track relay, a track} sectioina circuit for each signal, two sets of traflic'relays for controlling the circuits-0t the respective sets of opposing signals, two teed wires towhiclrthe sets traffic relays are respectively connected, 2:. return wire coininonxto both sets of relays, a source of current supply, and means for connecting either oi said feed wires with the source of current.

7. in a signaling system for single track railways, a] plurality of pairs *of opposing signals arran tul at intervals along a traclr, section, a circuit for each signal, two sets of tra'llic relays for controlling the circuits oi" the respective sets of opposing signals, two i'ecd wires to which-thc sets of tratlic relays are respectively connected, a source ofcun rent supply, a return wire common to all oi said relays, a switch for connecting either of said feed w' es with the source of current supply, and means for locking said switch against movement under predetermined contlitions.

8. In a. signaling system for single track *ailways, a plurality of pairs of opposing signals arranged at. intervals along a traclt section, a circuit for each signal, two sets of tratlic relays for controlling the circuits fot the respective sets oi? opposing signals, um feed wires to which the of traffic relays are respectively connected, :1 return wire common to all of said relays, a source hf current supply, a switch for connecting either of said feed wires with the source of current, an electrically controlled locking derice for said switch, and a circuit for said locking" device including the feted wire not connected to the said source of current.

in a signaling system for single track railways, a plurality of pairs of opposing signal tra'tlic relays for controlling; the circuits of the respective sets of opposing signals, a source of current supply, two circuits in which the respective sets of trafiic relays are included, a polarized relay in each ofsaid tra'iiic relay circuits, at pole-changer in said circuits, a switch for counectingeither of said circuits with the source of current, and

means torwfirstoperating said switch and subsequently the pole-changer.

10. in a signaling system for single track railways, a plurality of pairs of op nosing signals arranged at intervals along a track section, a. circuit for each signal, two setsof tratlic relays for controlling the circuits of the respective sets of opposing' signals, two

a, circuit for each si nal two sets of b 9 i; v

relays, and a switch in the circuit of each or"? said relays, operated by the movement of the signals controlled by the other set of relays.

11. In a signaling system. for single track railways, a section of track divided into a plurality o:t.l locks, a pair of opposing nals at each junction of adjacent blocks, a track relay for each pair of opposingsignals, a track battery for each pair of opposing signals, andtwo trafiic relays for each block, each of which is adapted to connect the rails of the block with a track buttery while the other connects the rails of the block with a track relay.

' 12. In a signaling system for single track railways, a sectionpf track divided into a plurality of blocks, a pair of opposing signals at each junction of adjacent blocks, a. track relay for each pair of signals, a plurality of track batteries for the section of track, and two trailic relays for each block, each of which is adapted to. connect the rails of the block with a track battery while the other connects the rails of the block'with a track relay.

13. In a rallway signaling system, a block section of a railway track, two track bat-- teries and two track relays for said block, and two traltic relays for said block, each of whichis adapted to connect the rails of the hloclr with one of the track batteries while the other connects the rails of the block with one of thetrack relays.

let, In a railway signaling system, a bloclc section of a railway. track, a track battery and time relay at each end of said block, and a trafltlc relay at each end of said block each of which-is adaptedto connect the rails V with a traclrbattery at one end of theiblock while the other connects the rails with a track relay atthe other end of thebloclc,

In testimony whereof I have signed my name to this specification in'the presence of- .two subscribing witnesses.

nnririrrsrurrrrsp V.

Witnesses M. 5.,Kmnmuo,

' A. L, VEZflCILLJ" 

